Executive brief
A vulnerability was identified in the Linux kernel's AMD display driver where the system could crash when initializing certain display connectors. This occurs because the software attempts to access memory associated with a display link that does not exist. In practice, this could lead to a system crash (Blue Screen or Kernel Panic) when certain monitors or display hardware are connected or initialized, impacting the availability of the workstation or server.
Technical details
A NULL pointer dereference exists in the amdgpu_dm_hpd_init() function within the AMD display driver (amdgpu). The vulnerability occurs because the code checks for a valid 'dc_link' pointer when deciding whether to use polling, but subsequently dereferences that same pointer unconditionally when setting up HPD interrupts. If a connector is encountered without a valid 'dc_link', the kernel will attempt to access an invalid memory address, leading to a kernel oops or panic. This issue has been resolved by moving the NULL check earlier in the initialization loop and skipping connectors that lack a valid link.
Affected products
- Linux Linux Kernel versions including 4562236b3bc0 and prior to fixed stable releases
Timeline
- 2026-02-06: other: Patch authored
- 2026-06-03: disclosed: CVE published